The present invention relates to semiconductor process chambers, and more particularly to particle removal following a process chamber wet clean.
Defect-free processing is paramount in semiconductor processing. Semiconductor processing tools must be free of defects/particles so that product yields are not impacted. Processing tools require cleaning, so that defect-free processing can be maintained. FIGS. 1a and 1b illustrate a prior art chamber cleaning process. Referring concurrently to both FIGS. 1a and 1b, a process chamber 10 is cleaned and wiped with a solvent (step 11) and then placed under vacuum (step 13). The disturbance of the solvent clean step can leave particles 12 inside the chamber 10 in areas, such as area 14, which are not accessible from the solvent wipe. Then, typically, a function known as cycle purge is performed on the chamber (step 15). A cycle purge creates a laminar flow through the chamber 10 by allowing a small amount of inert gas 16 through a single, cycle purge port 18 in the chamber 10 until a preset chamber pressure is achieved. The laminar flow is then turned off, and the chamber 10 is pumped down via pump 20 through open valve 22 to base pressure. This action of flowing gas and pumping down is repeated several times as a part of the cycle purge. Since the common method of cycle purging following solvent wipe does not always yield a particle free chamber, a better and more reliable method is needed so that manufacturing cost can be minimized.
The present invention addresses such a need.
The present invention provides aspects for more reliable particle removal from a semiconductor processing chamber following a chamber wet clean. With the present invention, an improved particle removal following wet cleans of semiconductor processing chambers occurs. The present invention creates a turbulent gas flow in a chamber in order to more thoroughly remove particles from the chamber, including those that the wet clean procedures cannot reach. In a straightforward and efficient manner, the turbulent gas flow is created by providing gas in both an upper and lower portion of the chamber substantially simultaneously, including the advantageous use of the backside helium available to chamber processing.
These and other advantages of the aspects of the present invention will be more fully understood in conjunction with the following detailed description and accompanying drawings.